Donald Trump will "say or do anything" in his campaign for the presidency, and his calls to restrict Muslims from entering the United States and advocating more surveillance on mosques are "aiding and abetting the enemy" when it comes to the fight against ISIS, former Defense Secretary and CIA Director Leon Panetta said Thursday.

"Of 50 years of public life, I have never experienced a major party candidate making the accusations claiming what Donald Trump raised," Panetta, also chief of staff for former President Bill Clinton, told MSNBC's Andrea Mitchell.

"When this country has been attacked, this country comes together, unifies and builds a consensus about how we protect ourselves in the future."

But Trump, after the attacks in Orlando last weekend, has done the exact opposite, said Panetta.

"He's not only accusing the president of the United States of treason and collaborating with the enemy, but what he's saying about restricting Muslims from coming into this country and doing surveillance on Muslim mosques is aiding and abetting the enemy. It is the most irresponsible and reckless kind of behavior that I have seen in a major presidential candidate."

Trump has also suggested, Mitchell noted, that soldiers in Iraq stole money sent to rebuild the country. His campaign clarified after that he was talking about Iraqi soldiers, she said, but "the Iraqis had nothing to do with the distribution of cash to Iraqis families who were injured of their forces there."

Panetta said he is "certainly" not aware of that happening, but told Mitchell that it's further proof that Trump will "say or do anything" to "create doubt and suspicion and divide us at a critical time when frankly we ought to be coming together, coming together on this investigation and coming together on law enforcement."

The issue, Panetta said, is to come together on preventing another attack, not divide Americans and "weaken this country even further."

Meanwhile, the United States is also facing the challenge of dealing with lone wolf attackers who have been influenced by extremists, either from exposure or through social media.

"The key is obviously, trying to get the American people as vigilant as possible about individuals in their community that show characteristics similar to what we saw of the individual in Orlando, that indicates he had a tendency to talk about the attack," said Panetta. "Those kind of individuals should be reported to law enforcement so we can take a step to hopefully prevent the lone wolf attack."

Donald Trump will "say or do anything" in his campaign for the presidency, and his calls to restrict Muslims from entering the United States and advocating more surveillance on mosques are "aiding and abetting the enemy" when it comes to the fight against ISIS, former ...